buffered_reader/
adapter.rs

1use std::io;
2
3use super::*;
4
5/// Changes the cookie type without introducing any buffering.
6///
7/// If you have a `b: BufferedReader<B>` but need a `c:
8/// BufferedReader<C>`, then one way to do that is to use `let c =
9/// Generic::with_cookie(b, _)`, but that introduces buffering.  This
10/// `Adapter` also changes cookie types, but does no buffering of its
11/// own.
12#[derive(Debug)]
13pub struct Adapter<T: BufferedReader<B>, B: fmt::Debug + Send + Sync, C: fmt::Debug + Sync + Send> {
14    _ghostly_cookie: std::marker::PhantomData<B>,
15    cookie: C,
16    reader: T,
17}
18
19assert_send_and_sync!(Adapter<T, B, C>
20                      where T: BufferedReader<B>,
21                            B: fmt::Debug,
22                            C: fmt::Debug);
23
24impl<T: BufferedReader<B>, B: fmt::Debug + Send + Sync, C: fmt::Debug + Sync + Send> fmt::Display for Adapter<T, B, C> {
25    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
26        f.debug_struct("Adapter").finish()
27    }
28}
29
30impl<T: BufferedReader<B>, B: fmt::Debug + Sync + Send> Adapter<T, B, ()> {
31    /// Instantiates a new adapter.
32    ///
33    /// `reader` is the source to wrap.
34    pub fn new(reader: T) -> Self {
35        Self::with_cookie(reader, ())
36    }
37}
38
39impl<T: BufferedReader<B>, B: fmt::Debug + Send + Sync, C: fmt::Debug + Sync + Send> Adapter<T, B, C> {
40    /// Like [`Self::new`], but sets a cookie.
41    ///
42    /// The cookie can be retrieved using the [`BufferedReader::cookie_ref`] and
43    /// [`BufferedReader::cookie_mut`] methods, and set using the [`BufferedReader::cookie_set`] method.
44    pub fn with_cookie(reader: T, cookie: C)
45            -> Adapter<T, B, C> {
46        Adapter {
47            reader,
48            _ghostly_cookie: Default::default(),
49            cookie,
50        }
51    }
52}
53
54impl<T: BufferedReader<B>, B: fmt::Debug + Send + Sync, C: fmt::Debug + Sync + Send> io::Read for Adapter<T, B, C> {
55    fn read(&mut self, buf: &mut [u8]) -> Result<usize, io::Error> {
56        self.reader.read(buf)
57    }
58}
59
60impl<T: BufferedReader<B>, B: fmt::Debug + Send + Sync, C: fmt::Debug + Sync + Send> BufferedReader<C> for Adapter<T, B, C> {
61    fn buffer(&self) -> &[u8] {
62        self.reader.buffer()
63    }
64
65    fn data(&mut self, amount: usize) -> Result<&[u8], io::Error> {
66        self.reader.data(amount)
67    }
68
69    fn consume(&mut self, amount: usize) -> &[u8] {
70        self.reader.consume(amount)
71    }
72
73    fn data_consume(&mut self, amount: usize) -> Result<&[u8], io::Error> {
74        self.reader.data_consume(amount)
75    }
76
77    fn data_consume_hard(&mut self, amount: usize) -> Result<&[u8], io::Error> {
78        self.reader.data_consume_hard(amount)
79    }
80
81    fn consummated(&mut self) -> bool {
82        self.reader.consummated()
83    }
84
85    fn get_mut(&mut self) -> Option<&mut dyn BufferedReader<C>> {
86        None
87    }
88
89    fn get_ref(&self) -> Option<&dyn BufferedReader<C>> {
90        None
91    }
92
93    fn into_inner<'b>(self: Box<Self>) -> Option<Box<dyn BufferedReader<C> + 'b>>
94        where Self: 'b {
95        None
96    }
97
98    fn cookie_set(&mut self, cookie: C) -> C {
99        std::mem::replace(&mut self.cookie, cookie)
100    }
101
102    fn cookie_ref(&self) -> &C {
103        &self.cookie
104    }
105
106    fn cookie_mut(&mut self) -> &mut C {
107        &mut self.cookie
108    }
109}
buffered_reader/adapter.rs

buffered_reader/
adapter.rs
